If you do not have an ophthalmologist, or if you are away from home, find a teaching hospital that has a training program in ophthalmology, go to their emergency room, and ask to see the eye resident on call. This chapter describes several examples of each type of eye problem.
During transcription, enzymes called RNA polymerases build RNA molecules that are complementary to a portion of one strand of the DNA double helix (Figure 3). Figure 3: RNA polymerase at work. RNA polymerase (green) synthesizes a strand of RNA that is complementary to the DNA template strand below it.
1 Transcribing DNA to MRNA Transcription refers to the synthesis of RNA (mRNA or tRNA) from a one strand of DNA. 2  Messenger RNA (mRNA) carries the genetic information from DNA to the ribosomes to syntheâ¦. 3  Transcription Termination Transcription termination is the last step in gene expression.